Drum washing machine



FIG. 1 is a front view of my new design for a drum washing machine;

FIG. 2 is a left side view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a rear view thereof; and,

FIG. 5 is a top view thereof.

The broken lines shown in the drawings represent portions of the drum washing machine that form no part of the claimed design. 

CLAIM The ornamental design for a drum washing machine, as shown and described. 